Production of nitro compounds



. Patented Mar. 23, 1943 2.314.815 rnonmmon or nrrao comonuns Reginald George Franklin and Wilkins,Norton-on-Tees, I 1- Chemical Industries Limited, at

Imperial ration of Great Britain.

No Drawing. Application No. 839.80%. In Great M James oreto I c n -p Frederick 11, 1940, Serial June - July 135, 1939 4 Claims. (i. sec-s44) This invention relates to the manufacture of nitro compounds, in particular of di-nitro derivatives of oleflnes.

One object of the invention is. toprov do process for the production oi mtro-oleiines,

especially dinitro-olefines. Another object is to provide a process for reacting butadiene with 1 nitrogen dioxide under controlled temperature conditions. A further object -is to provide new nitro compounds. Further objects will appear hereinafter.

The crystals thus obtained can be stored at the temperature of solid carbon dioxide, but they change slowly toa dark liquid at room temperathere is a danger of explosion.

According to the present invention aliphatic hydrocarbons having conjugated double bonds are treated with liquid or gaseous nitrogen dioxide or with gaseous mixtures containing nitrogen dioxide.

The process of this invention is not restricted in its application to a pure aliphatic hydrocarbon'having conjugated double bonds, or to mixtures of such hydrocarbons, but may also be applied to the saidhydrocarbons when containing such impurities as may result from their manulecture. ,The reaction may be carriedout either in the vapor phase or inthe liquid phase. When" working in the liquid phase it isdesirable'to employ a solvent for the hydrocarbon and the nitrogen dioxide. Inert gases, such as carbon dioxide and nitrogen, and inert hydrocarbons such as methane, may advantageously be used as dilucnts to control the reaction, especially when working appreciably above atmospheric temperature.

s The following examples illustrate of the present invention.

Example 1 i4 parts by weight or pure dry liquid nitrogen dioxide were dissolved in 36 parts by weight of the process sodium-dried ether'and added gradually to parts by weight of liquid butadiene dissolved in 36 parts by weight of dried ether containcdin a vessel cooled in ice and salt. The liquid was kept crop of crystals.

ture. On complete removal of ether irom the ethereal filtrate, a di-nitro butylene in the term of a ra oil is left, which goes almost solid on standing for some'days. The complete removal oi the ether must be done carefully The reaction can be carried out in the manner indicated abovev with carbon tetrachloride or ligroln' instead of ether as a solvent, but a dimtro 'butyiene in the form of a red oil iathcn obtained. The red oil so produced'is iairly'stabie" at 0 C. but tends to ignite on contact with air.

trample z 1 volume oi, butadiene was reacted in the gaseous phase with rather less than 2 volumes of nitrogen dioxide in the presence oi carbon dioxide at a'tempcrature of -85 C. The gaseous reactants, each'diluted with hon dioxide water jacket and fitted with a drain tap in an amount such that the total volume of carbon dioxide to the total volume of reactants was in the ratio of :15, impinged side by side through lets on to the-bulb of a. thermometer in a reaction vessel surrounded by a, circulating v for frequent removal oi the product.

' A di-nitro butylene in the form of a fluid oil.

was thus obtained and collectedin-a tube cooled by ice. Solid yellow crystals as produced in Example 1 can be obtained from the fluid oil by treating it with ether or ethyl alcohol.

The fluid oil is converted partially into a solid .(probably a polymer of a di-nitro 'butylene) when stored at low temperature in ice or solid carbon dioxide, but thcsolid reverts to the liquid tormon heating to 35 C. for about one hour.

7 The oil can be kept at 35 C. for several hours,

but with prolonged heating it darkens slowly and becomes unstable.

The fluid oil referred to above is believed to be 1:4. di-nitro p-butylene and had a molecular weight of in acetone. It was partly soluble in water. the aqueous layer having a pH of 8. It

' was completely soluble in methanol and in acetic acid. It dissolved in ethyl alcohol to give a brown solution and a yellow precipitate oi melting point 56 C. When treated with ethyl ether, it gave a yellow precipitate of melting point 58 C. The yellow precipitate appears to be the aciform of the di-nitrc butylene.

Compounds oi this general type are characwhen by utility in a number of was. minstance. they serve as solvento' io'r cellulose derivotives and the like, asint-ermedintes in the manufacture oi certain dinmino compounds and posseseinsecticidai 'properties. Other hydrocarbons which may be reacted in accordance with the invention lnclude-iaoprene.- -methyl ieoprene a.nd other homologue; of

isoprene; v

As many widely diiierent embodiments of thin invention may be made without departing from the spirit or scope thereof, it is to be undemtoodthat we do not limitourselves to the apeciflcembodiments thereof, except appended claims We claim:

as defined in the" I 2. 'rhe p'roeeu of nitrolen dioxide with butadicne which compriseyintermihiiini the nitrogen dioxide withbutadiene in the prelence 0!. a gaseous inert diluent.

3."!he process of reacting nitrogen dioxide with butadiene which compria'es dissolving llld nitrogen dioxide and sa d butediene in a common' solvent and intermingling meme in aidv liquid phase. 7

ji. The process oi reeetingdioxide with butndiene in upore phaee whichcomnriael diluting Imoua'nitroun dioxide'with an inert '1. A; a new chemical compound 1,i-dinitro-- n zas diiutin: Icseous bgitadiene with mumgas and interminzlinz uiddiluted nitrogen dioxide with-said diluted butadiene in mmnm mm mm. e 

